pset5 recover.c Version 1

gistfile1.c

/**
 * recover.c
 *
 * Computer Science 50
 * Problem Set 5
 *
 * Recovers JPEGs from a forensic image.
 */
 
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>

#include "bmp.h"

int main(void)
{
    // opens card.raw
    FILE* inptr = fopen("card.raw", "r");
    if ("inptr" == NULL)
    {
        printf("Could not open card.raw");
        return 1;
    }
    
    int counter = 1;
    char title[7];
    sprintf(title, "%.3i.jpg", counter);
    FILE* img = fopen(title, "a");
    
    while (true)
    {
        BYTE JPEG[512];
 
        fread(&JPEG, 512 * sizeof(BYTE), 1, inptr);
 
        if (JPEG[0] == 0xff && JPEG[1] == 0xd8 && JPEG[2] == 0xff)
        {
            if (JPEG[3] == 0xe0 || JPEG[3] == 0xe1)
            {
                if (counter == 1)
                {
                    fwrite(&JPEG, 512 * sizeof(BYTE), 1, img);
                    
                    while (true)
                    {
                        BYTE JPEG[512];
                        fread(&JPEG, 512 * sizeof(BYTE), 1, inptr);
                        
                        if (JPEG[0] == 0xff && JPEG[1] == 0xd8 && JPEG[2] == 0xff)
                        {
                            if (JPEG[3] == 0xe0 || JPEG[3] == 0xe1)
                            {
                                fclose(img);
                                counter++;
                                sprintf(title, "%.3i.jpg", counter);
                                FILE* img = fopen(title, "a");
                                fwrite(&JPEG, 512 * sizeof(BYTE), 1, img);
                                break;
                            }
                        }
                        
                        else
                        {
                            fwrite(&JPEG, 512 * sizeof(BYTE), 1, img);
                        }
                    }
                }
                  
                else
                {
                    fclose(img);
                    counter++;
                    sprintf(title, "%.3i.jpg", counter);
                    FILE* img = fopen(title, "a");
                    fwrite(&JPEG, 512 * sizeof(BYTE), 1, img);
                }
            }
        }
          
        if (counter != 1)
        {
            fwrite(&JPEG, 512 * sizeof(BYTE), 1, img);
        }
            
        if (feof(inptr))
        {
            fclose(img);
            break;
        }
    }
    
    // closes card.raw
    fclose(inptr);
}